• Black root rot of cucurbits

  General Phomopsis sclerotioides is a plant pathogen infecting cucurbits, causing black root rot of cucurbits. Damage symptoms Phomopsis sclerotioides causes grey-black spots with a dark demarcation line on cucumber roots. The lesions are slightly sunken and are mostly formed around the point of attachment of lateral roots and root hairs. The lesions may grow and encircle the root. The roots become yellow-brown to black and ultimately die. Black

• Root and crown rot of strawberry

  General New diseases in strawberry have been ascribed to Pestalotiopsis clavispora in the case of root and crown rot (of strawberry), first found in The Netherlands, and Pestalotiopsis longisetula in the case of leaf spots, such as leaf spot of strawberry and fruit rot reported mainly from Brazil. The genus is quite complex, so the taxonomy may change. Pestalotiopsis clavispora is also called Neopestalotiopsis clavispora. Pestalotiopsis clavispora

• Pea blight, leaf and pod spot

  General Ascochyta pisi is a fungal plant pathogen that causes A scochyta blight on pea (leaf blight or pea blight) and lesions of stems, leaves, and pods (pea leaf spot and pea pod spot). Damage symptoms Ascochyta pisi causes spots on leaves, stems and pods of peas. The spots on leaves and pods are round, on the stems they are more elongated. The lesions are light brown, sunken and surrounded by a dark brown to red-brown border. The first infection

• Black rot of carrots

  General The only known stage in all Alternaria species is the asexual stage. Conidia and mycelium overwinter in the soil and on crop residues and cause primary infection of the leaves. Survival can be several years, in the case of black rot of carrots ( Alternaria radicina ) up to 8 years. Damage symptoms Black rot of carrots ( Alternaria radicina ) causes death of seedlings and dark brown lesions with a yellow halo on leaves, growing into crown

• Bacterial wilt, brown rot

  General Ralstonia solanacearum is a plant pathogenic bacterium. It is a soil-borne disease and colonises the xylem, causing bacterial wilt and brown rot in a very wide range of potential host plants. Damage symptoms In potato, field symptoms of Ralstonia solanacearum are wilting and yellowing of leaves and stunted plants. Inside, vascular browning is common with bacterial slime oozing from the cut. When the bacteria transfers to young plants

• Crazy roots, hairy roots, crown gall

  General Rhizobium bacteria are soil bacteria that fix nitrogen after becoming established inside root nodules of legumes. Additionally, pathogenic Agrobacterium s pecies have recently been assigned to the genus Rhizobium . These pathogenic bacteria were formerly known as Agrobacterium tumefaciens or Agrobacterium radiobacter, Agrobacterium vitis, Agrobacterium rhizogenes and Agrobacterium rubi, n ow the first part of the name is changed to

• Cottony soft rot

  General Sclerotinia sclerotiorum, also known as cottony soft root, is a plant pathogenic fungus. It has a very wide range of host plants. Damage symptoms The first symptoms of a cottony soft root ( Sclerotinia sclerotiorum ) infection are water-soaked lesions at the stem base. The plant above it wilts and rots. White, fluffy fungal mycelium grows on the lesions, giving this disease its name cottony soft rot. In the mycelium, big, dark sclerotia are

• Wheat bunt

  General Tilletia tritici and Tilletia laevis only differ in one gene and easily hybridize. There is debate whether they should indeed be considered separate species, since they cause the exact same symptoms. Tilletia tritici and Tilletia laevis cause diseases such as common wheat bunt, stinking smut, karnal bunt of wheat. Damage symptoms Plantsinfected by Tilletia tritici and Tilletia laevis are hard to distinguish from infected plants before head

• Charcoal rot

  General Macrophomina phaseolina is a common soil fungus in warmer regions, causing charcoal rot. It has a very wide range of host crops, many of which are economically important food crops. Damage symptoms In strawberry, this pathogen causes wilting of foliage, stunting of plants and drying and death of older leaves. The youngest central leaves usually remain unaffected and stay green. The first symptoms are mostly found after plants are well

• Black sigatoka disease

  General Mycosphaerella fijiensis also known as black sigatoka, is an ascomycete fungus that causes leaf-spot of banana. Damage symptoms Black sigatoka (Mycosphaerella fijiensis ) first causes small, light yellow spots or streaks on leaves of about one month old. The symptoms run parallel to the veins. Within a few days, the spots become a few centimetres in size and turn brown with light grey centres. These spots enlarge further and the tissue around